imaginary part

American  

noun

Mathematics.

1. the coefficient b in the complex number a + bi.

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imaginary part British  

noun

1. the coefficient b in a complex number a + i b , where i = √–1

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Etymology

Origin of imaginary part

First recorded in 1925–30

Example Sentences

See Examples For:

imaginary part

In the mathematical description of a quantum state, the real part represents the amplitude, while the imaginary part represents the phase.

From Science Daily ● Jul. 13, 2026

Phoenix was imaginary, part of a 2009 government preparation exercise for a killer hurricane dubbed Project Phoenix — an exercise updated in 2020 focusing on small business recovery.

From Seattle Times ● Sep. 27, 2022

Let’s consider the number The real part of the complex number is and the imaginary part is We plot the ordered pair to represent the complex number as shown in Figure 1.

From Textbooks ● Dec. 1, 2021

This term is called the complex conjugate of the denominator, which is found by changing the sign of the imaginary part of the complex number.

From Textbooks ● Feb. 13, 2015

The horizontal axis represents the real part of the complex number, while the vertical axis represents the imaginary part.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife